Java example source code file (Basic.java)

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Java - Java tags/keywords

days, filetime, hours, instant, max_second, microseconds, milliseconds, minutes, nanoseconds, nullpointerexception, random, runtimeexception, string, threading, threads, timeunit, util

The Basic.java Java example source code

/*
 * Copyright (c) 2009, 2013, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

/* @test
 * @bug 6844313 8011647
 * @summary Unit test for java.nio.file.FileTime
 */


import java.nio.file.attribute.FileTime;
import java.time.Instant;
import java.util.concurrent.TimeUnit;
import static java.util.concurrent.TimeUnit.*;
import java.util.Random;
import java.util.EnumSet;

public class Basic {

    static final Random rand = new Random();

    public static void main(String[] args) {
        long now = System.currentTimeMillis();
        long tomorrowInDays = TimeUnit.DAYS.convert(now, MILLISECONDS) + 1;
        long yesterdayInDays = TimeUnit.DAYS.convert(now, MILLISECONDS) - 1;

        Instant nowInstant = Instant.ofEpochMilli(now);

        // equals
        eq(now, MILLISECONDS, now, MILLISECONDS);
        eq(now, MILLISECONDS, now*1000L, MICROSECONDS);
        neq(now, MILLISECONDS, 0, MILLISECONDS);
        neq(now, MILLISECONDS, 0, MICROSECONDS);

        eq(nowInstant, now, MILLISECONDS);
        eq(nowInstant, now*1000L, MICROSECONDS);
        neq(nowInstant, 0, MILLISECONDS);
        neq(nowInstant, 0, MICROSECONDS);

        // compareTo
        cmp(now, MILLISECONDS, now, MILLISECONDS, 0);
        cmp(now, MILLISECONDS, now*1000L, MICROSECONDS, 0);
        cmp(now, MILLISECONDS, now-1234, MILLISECONDS, 1);
        cmp(now, MILLISECONDS, now+1234, MILLISECONDS, -1);

        cmp(tomorrowInDays, DAYS, now, MILLISECONDS, 1);
        cmp(now, MILLISECONDS, tomorrowInDays, DAYS, -1);
        cmp(yesterdayInDays, DAYS, now, MILLISECONDS, -1);
        cmp(now, MILLISECONDS, yesterdayInDays, DAYS, 1);
        cmp(yesterdayInDays, DAYS, now, MILLISECONDS, -1);

        cmp(Long.MAX_VALUE, DAYS, Long.MAX_VALUE, NANOSECONDS, 1);
        cmp(Long.MAX_VALUE, DAYS, Long.MIN_VALUE, NANOSECONDS, 1);
        cmp(Long.MIN_VALUE, DAYS, Long.MIN_VALUE, NANOSECONDS, -1);
        cmp(Long.MIN_VALUE, DAYS, Long.MAX_VALUE, NANOSECONDS, -1);

        cmp(Instant.MIN, Long.MIN_VALUE, DAYS, 1);
        cmp(Instant.MIN, Long.MIN_VALUE, HOURS, 1);
        cmp(Instant.MIN, Long.MIN_VALUE, MINUTES, 1);
        cmp(Instant.MIN, Long.MIN_VALUE, SECONDS, 1);
        cmp(Instant.MIN, Instant.MIN.getEpochSecond() - 1, SECONDS, 1);
        cmp(Instant.MIN, Instant.MIN.getEpochSecond() - 100, SECONDS, 1);
        cmp(Instant.MIN, Instant.MIN.getEpochSecond(), SECONDS, 0);

        cmp(Instant.MAX, Long.MAX_VALUE, DAYS, -1);
        cmp(Instant.MAX, Long.MAX_VALUE, HOURS, -1);
        cmp(Instant.MAX, Long.MAX_VALUE, MINUTES, -1);
        cmp(Instant.MAX, Long.MAX_VALUE, SECONDS, -1);
        cmp(Instant.MAX, Instant.MAX.getEpochSecond() + 1, SECONDS, -1);
        cmp(Instant.MAX, Instant.MAX.getEpochSecond() + 100, SECONDS, -1);
        cmp(Instant.MAX, Instant.MAX.getEpochSecond(), SECONDS, 0);

        cmp(nowInstant, now, MILLISECONDS, 0);
        cmp(nowInstant, now*1000L, MICROSECONDS, 0);
        cmp(nowInstant, now-1234, MILLISECONDS, 1);
        cmp(nowInstant, now+1234, MILLISECONDS, -1);
        cmp(nowInstant, tomorrowInDays, DAYS, -1);
        cmp(nowInstant, yesterdayInDays, DAYS, 1);

        // to(TimeUnit)
        to(MILLISECONDS.convert(1, DAYS) - 1, MILLISECONDS);
        to(MILLISECONDS.convert(1, DAYS) + 0, MILLISECONDS);
        to(MILLISECONDS.convert(1, DAYS) + 1, MILLISECONDS);
        to(1, MILLISECONDS);
        to(0, MILLISECONDS);
        to(1, MILLISECONDS);
        to(MILLISECONDS.convert(-1, DAYS) - 1, MILLISECONDS);
        to(MILLISECONDS.convert(-1, DAYS) + 0, MILLISECONDS);
        to(MILLISECONDS.convert(-1, DAYS) + 1, MILLISECONDS);
        for (TimeUnit unit: TimeUnit.values()) {
            for (int i=0; i<100; i++) { to(rand.nextLong(), unit); }
            to(Long.MIN_VALUE, unit);
            to(Long.MAX_VALUE, unit);
        }

        // toInstant()
        int N = 1000;
        for (TimeUnit unit : EnumSet.allOf(TimeUnit.class)) {
            for (int i = 0; i < N; i++) {
                long value = rand.nextLong();
                FileTime ft = FileTime.from(value, unit);
                Instant instant = ft.toInstant();
                if (instant != Instant.MIN && instant != Instant.MAX) {
                    eqTime(value, unit, instant);
                }
            }
        }
        for (TimeUnit unit : EnumSet.allOf(TimeUnit.class)) {
            long value = Long.MIN_VALUE;
            FileTime ft = FileTime.from(value, unit);
            Instant instant = ft.toInstant();
            if (unit.compareTo(TimeUnit.SECONDS) < 0) {
                eqTime(value, unit, instant);
            } else if (!instant.equals(Instant.MIN)) {
                throw new RuntimeException("should overflow to MIN");
            }
            value = Long.MAX_VALUE;
            ft = FileTime.from(value, unit);
            instant = ft.toInstant();
            if (unit.compareTo(TimeUnit.SECONDS) < 0) {
                eqTime(value, unit, instant);
            } else if (!instant.equals(Instant.MAX)) {
                throw new RuntimeException("should overflow to MAX");
            }
        }

        // from(Instant)
        final long MAX_SECOND = 31556889864403199L;
        for (int i = 0; i < N; i++) {
            long v = rand.nextLong();
            long secs = v % MAX_SECOND;
            Instant instant = Instant.ofEpochSecond(secs, rand.nextInt(1000_000_000));
            FileTime ft = FileTime.from(instant);
            if (!ft.toInstant().equals(instant) || ft.to(SECONDS)  != secs) {
                throw new RuntimeException("from(Instant) failed");
            }
            long millis = v;
            instant = Instant.ofEpochMilli(millis);
            ft = FileTime.from(instant);
            if (!ft.toInstant().equals(instant) ||
                ft.toMillis()  != instant.toEpochMilli()) {
                throw new RuntimeException("from(Instant) failed");
            }
            long nanos = v;
            ft = FileTime.from(nanos, NANOSECONDS);
            secs = nanos / 1000_000_000;
            nanos = nanos % 1000_000_000;
            instant = Instant.ofEpochSecond(secs, nanos);
            if (!ft.equals(FileTime.from(instant))) {
                throw new RuntimeException("from(Instant) failed");
            }
        }

        // toString
        ts(1L, DAYS, "1970-01-02T00:00:00Z");
        ts(1L, HOURS, "1970-01-01T01:00:00Z");
        ts(1L, MINUTES, "1970-01-01T00:01:00Z");
        ts(1L, SECONDS, "1970-01-01T00:00:01Z");
        ts(1L, MILLISECONDS, "1970-01-01T00:00:00.001Z");
        ts(1L, MICROSECONDS, "1970-01-01T00:00:00.000001Z");
        ts(1L, NANOSECONDS, "1970-01-01T00:00:00.000000001Z");
        ts(999999999L, NANOSECONDS, "1970-01-01T00:00:00.999999999Z");
        ts(9999999999L, NANOSECONDS, "1970-01-01T00:00:09.999999999Z");

        ts(-1L, DAYS, "1969-12-31T00:00:00Z");
        ts(-1L, HOURS, "1969-12-31T23:00:00Z");
        ts(-1L, MINUTES, "1969-12-31T23:59:00Z");
        ts(-1L, SECONDS, "1969-12-31T23:59:59Z");
        ts(-1L, MILLISECONDS, "1969-12-31T23:59:59.999Z");
        ts(-1L, MICROSECONDS, "1969-12-31T23:59:59.999999Z");
        ts(-1L, NANOSECONDS, "1969-12-31T23:59:59.999999999Z");
        ts(-999999999L, NANOSECONDS, "1969-12-31T23:59:59.000000001Z");
        ts(-9999999999L, NANOSECONDS, "1969-12-31T23:59:50.000000001Z");

        ts(-62135596799999L, MILLISECONDS, "0001-01-01T00:00:00.001Z");
        ts(-62135596800000L, MILLISECONDS, "0001-01-01T00:00:00Z");
        ts(-62135596800001L, MILLISECONDS, "-0001-12-31T23:59:59.999Z");

        ts(253402300799999L, MILLISECONDS, "9999-12-31T23:59:59.999Z");
        ts(-377642044800001L, MILLISECONDS, "-9999-12-31T23:59:59.999Z");

        // NTFS epoch in usec.
        ts(-11644473600000000L, MICROSECONDS, "1601-01-01T00:00:00Z");

        ts(Instant.MIN, "-1000000001-01-01T00:00:00Z");
        ts(Instant.MAX, "1000000000-12-31T23:59:59.999999999Z");

        try {
            FileTime.from(0L, null);
            throw new RuntimeException("NullPointerException expected");
        } catch (NullPointerException npe) { }
        try {
            FileTime.from(null);
            throw new RuntimeException("NullPointerException expected");
        } catch (NullPointerException npe) { }

        FileTime time = FileTime.fromMillis(now);
        if (time.equals(null))
            throw new RuntimeException("should not be equal to null");
        try {
            time.compareTo(null);
            throw new RuntimeException("NullPointerException expected");
        } catch (NullPointerException npe) { }

        // Instant + toMilli() overflow
        overflow(Long.MAX_VALUE,
                 FileTime.from(Instant.MAX).toMillis());
        overflow(Long.MAX_VALUE,
                 FileTime.from(Instant.ofEpochSecond(Long.MAX_VALUE / 1000 + 1))
                         .toMillis());
        overflow(Long.MIN_VALUE,
                 FileTime.from(Instant.MIN).toMillis());
        overflow(Long.MIN_VALUE,
                 FileTime.from(Instant.ofEpochSecond(Long.MIN_VALUE / 1000 - 1))
                         .toMillis());

        // Instant + to(TimeUnit) overflow
        overflow(Long.MAX_VALUE,
                 FileTime.from(Instant.ofEpochSecond(Long.MAX_VALUE / 1000 + 1))
                         .to(MILLISECONDS));
        overflow(Long.MAX_VALUE,
                 FileTime.from(Instant.ofEpochSecond(Long.MAX_VALUE / 1000,
                                                     MILLISECONDS.toNanos(1000)))
                    .to(MILLISECONDS));
        overflow(Long.MIN_VALUE,
                 FileTime.from(Instant.ofEpochSecond(Long.MIN_VALUE / 1000 - 1))
                         .to(MILLISECONDS));
        overflow(Long.MIN_VALUE,
                 FileTime.from(Instant.ofEpochSecond(Long.MIN_VALUE / 1000,
                                                     -MILLISECONDS.toNanos(1)))
                         .to(MILLISECONDS));
    }

    static void overflow(long minmax, long v) {
        if (v != minmax)
            throw new RuntimeException("saturates to Long.MIN/MAX_VALUE expected");
    }

    static void cmp(long v1, TimeUnit u1, long v2, TimeUnit u2, int expected) {
        int result = FileTime.from(v1, u1).compareTo(FileTime.from(v2, u2));
        if (result != expected)
            throw new RuntimeException("unexpected order");
    }

    static void cmp(Instant ins, long v2, TimeUnit u2, int expected) {
        int result = FileTime.from(ins).compareTo(FileTime.from(v2, u2));
        if (result != expected)
            throw new RuntimeException("unexpected order");
    }

    static void eq(long v1, TimeUnit u1, long v2, TimeUnit u2) {
        FileTime t1 = FileTime.from(v1, u1);
        FileTime t2 = FileTime.from(v2, u2);
        if (!t1.equals(t2))
            throw new RuntimeException("not equal");
        if (t1.hashCode() != t2.hashCode())
            throw new RuntimeException("hashCodes should be equal");
    }

    static void eq(Instant ins, long v2, TimeUnit u2) {
        FileTime t1 = FileTime.from(ins);
        FileTime t2 = FileTime.from(v2, u2);
        if (!t1.equals(t2))
            throw new RuntimeException("not equal");
        if (t1.hashCode() != t2.hashCode())
            throw new RuntimeException("hashCodes should be equal");
    }

    static void eqTime(long value, TimeUnit unit, Instant instant) {
        long secs = SECONDS.convert(value, unit);
        long nanos = NANOSECONDS.convert(value - unit.convert(secs, SECONDS), unit);
        if (nanos < 0) {    // normalize nanoOfSecond to positive
            secs -= 1;
            nanos += 1000_000_000;
        }
        if (secs != instant.getEpochSecond() || (int)nanos != instant.getNano()) {
            System.err.println(" ins=" + instant);
            throw new RuntimeException("ft and instant are not the same time point");
        }
    }

    static void neq(long v1, TimeUnit u1, long v2, TimeUnit u2) {
        FileTime t1 = FileTime.from(v1, u1);
        FileTime t2 = FileTime.from(v2, u2);
        if (t1.equals(t2))
            throw new RuntimeException("should not be equal");
    }

    static void neq(Instant ins, long v2, TimeUnit u2) {
        FileTime t1 = FileTime.from(ins);
        FileTime t2 = FileTime.from(v2, u2);
        if (t1.equals(t2))
            throw new RuntimeException("should not be equal");
    }

    static void to(long v, TimeUnit unit) {
        FileTime t = FileTime.from(v, unit);
        for (TimeUnit u: TimeUnit.values()) {
            long result = t.to(u);
            long expected = u.convert(v, unit);
            if (result != expected) {
                throw new RuntimeException("unexpected result");
            }
        }
    }

    static void ts(long v, TimeUnit unit, String expected) {
        String result = FileTime.from(v, unit).toString();
        if (!result.equals(expected)) {
            System.err.format("FileTime.from(%d, %s).toString() failed\n", v, unit);
            System.err.format("Expected: %s\n", expected);
            System.err.format("     Got: %s\n", result);
            throw new RuntimeException();
        }
    }

    static void ts(Instant instant, String expected) {
        String result = FileTime.from(instant).toString();
        if (!result.equals(expected)) {
            System.err.format("FileTime.from(%s).toString() failed\n", instant);
            System.err.format("Expected: %s\n", expected);
            System.err.format("     Got: %s\n", result);
            throw new RuntimeException();
        }
    }
}